SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed23fad4969e9d6dfc1fcbc37f5fb6b714f57153c60a394f10be94b3cfba9f65' 
  AND token = '42QmS0/7TXb58VRQHb0vOPcyUbjdblLM6s45VzjsTLI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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