SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '17778f5430075ab51f3a1f9c5286410f31d19638a6a1cd316c023392d70e67bb' 
  AND token = 'g/cXweWMqIkjgaGQNYAPpPFnURWAI+RuIa3uMMHObBc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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