SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2a578e77bac270e64430744566d5f88a2d9f0e19db412321536a05a9fb45d69' 
  AND token = 'ppJwJdJw9Q4DJ/OE+S9G6ZNRo0Usiowq+Y1ihuVV0VA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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