SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e74a05afb768bf39dd1a4ba9a79c224f21afcf4332bfe7f4c90a256bdeb484de' 
  AND token = 'FrHyIT+FetO191cbZFRsInz5T2ePteul5mmDiyr5bsw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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