SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '757c124043360fb28237d752e958222e4f2a9b629731847fc8f4fa1d0ebb7ccf' 
  AND token = '9h5TLUHdvgZHL7B3Ix/X1PFSrPjSUP4jsckZhMoDtmY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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