SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '43f13faa760e4617319ac52a234e5c053eb2f2dc8b36e1df3eb899cc9547b9f0' 
  AND token = 'Fohbbi6X1Ck447dGRrVDCehRFZ2Ovdt6sJGhrEFFUYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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