SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a1ac3962afb3eafac91440648a6b27084fc6cb0b24cbbfdad19cfeeb2303fcc' 
  AND token = 'eMPCwXFiRSzaG3+91ShvRve9ogCFy/vTjpu3wLaQxo8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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