SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '811f2b6dbf4122a7a122ae0ada92a39b5ae43918165ca1cc958341499b478bbd' 
  AND token = 'a9ifFil/hBALnkoJyc83PhwVD1sQlhfnno/2x6VwYSs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}