SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e3c7e7459847a315af416034a8a95ba8d1a04f6e10bf555eb208af678517007' 
  AND token = 'fuW0cAajrfPqaleAI9hJ+dECAd1J3rur7jxt3VF4F/w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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