SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'adc03afe4eeee75a7622bf8ef23b5fb1bd736f54c25f85a867990a51d5c162a2' 
  AND token = 'vLbBdFXyKz0wDcx949orSQjqqXbiI8XjW1JI0/joPww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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