SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94f6f55f268496c3c8fd7a36fa1c30dd32d73f55ccc8a4bf6fdae8a4e06c474b' 
  AND token = 'CrgS9iJSjoKKuxOwSqYBzrb8gnj1LqhSmIPs7xyGS7U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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