SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9765327c237db6886aa78d7311c5328b42c88280d15f37cec18766a740191e7d' 
  AND token = 'm9OWZq5+KiCW/nvKvi0PCeV3LWBZP7hH9j26VdKN0QE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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