SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7de82125ff91f62e60ef1fb13cfa8bb3e417ea144695fbe7464fd93d63dee7cf' 
  AND token = '6HzAdtNc8APrtUajNEZ5n3Jl0JxOkmnlpvnfwFFD1Hc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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