SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c5cd48df8e5204946e1d9bdc5965421d3f387c009dd9c3b9d7fdeccd6724a46' 
  AND token = 'gNMtzkYYfPErLc6ZvzbwSTajEBEDPvjFrqGxcLZHP+U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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