SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88b7c4ddc73036eb6779ade6137614b11e6024967f255b351a94e8dabbb5d344' 
  AND token = 'rOkQziCcb3OjoJV6sh8wlvPu7NP6L/LVxJhFDFmB/FY=' 
  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"
    }
  }
}