SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd3f0af4a9aa9a61ffc3798820b93794b5eece72236cf9098f4f02e1bf5ff8ff' 
  AND token = 'EKnkvZq0r8E1lAhZIY3kvGGLTxVzqmgRT4D5flJggWM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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