SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '110d470b16971323fdbcc049f120e4eefeceed9df2618a1c4196f4c8ca158be6' 
  AND token = 'KUbTksfUbyksdtVsxxjuCEY5UTF4FoV+rhx2crZcvQI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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