SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a279ee9efd5cad78410e2328ad5641df4d6764afc1478d27dc4b9040d1755e7' 
  AND token = 'g/2psmkduCC9pG6aNRISh1blQI7sP/JqNeDw+MKzUNU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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