SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cda2cac6311a8b67faa1e454624c7f40bd87e563a77097616c452c70e38b056c' 
  AND token = 'FgDe8K8vepDSb3ISZsHmaAfAKABf6wELkxi0T1Bb+UU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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