SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e753f9faa14274b9c12f70b33f492c39feaf9f47f389922898a71d0b807b6d16' 
  AND token = 'JVXAYDyZZhIQk5hEJ+qSBOPM+Qq1A55nxLY2+Fa/fdc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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