SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '530170eb50f8e87a2b4cd4cfe533c493bf39b7d5f7d424578f2a4f9c86f72fbd' 
  AND token = 'JUjTi0TCZ4rkvIRLAJJGq53fVG8IHqhA3jUkrZ6K0jg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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