SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd4e7b56b8081303fa466e28ef900d59f29b3ab940846090830dfe1c8f3c50f8d' 
  AND token = 'DZ2MzsNQ7CxKEltrnhPycBFB+ZVtJdT8xB9xlfdWkdQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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