SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9385949f54826e0117fc0eaf9ade77771953c579d364f829eaeefb6355c554a9' 
  AND token = 'ICOKVyd8NmNvhDIQlSW/K2FdnaqWvRlEDFcFWJWHXWY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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