SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9bdd4f3c1ee3478b033bf1852b28d838591ca3433f74ec7d4cb8544d3fc3588' 
  AND token = 'R/lVmDUV0zlFuDSWj3yaoNzk8Oxay35BlA6vJJJZ4fY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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