SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ec03f3db5b4389e825d3980cad6978543469400fe96215c72b2fe536f6155ae' 
  AND token = 'FZNs0wSuwJfhAfRtgodD/GQI1p9MQeR0hGD/SQK2SKQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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