SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b48953f9bc27a16b26b7fba18f6f55d26b92e8d65281595103b3f8a8a82e83b0' 
  AND token = 'nDukIE0C4hOSBPYqWF0ZYc71Ps+wt/+4nCE0n2ps/tc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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