SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '75cb7cefb646ad8db91a04cf613bbc21c62b99cafc9e36403f4c8cba3e9b6d17' 
  AND token = 'WFNIkTOXZwKrNhbBeSKy7fk3Tb2rWxvjz4k2ojMkYBE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}