SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9c58969c307abafbe20c9486890c426f07d9d1f64f7d513f43625ea75cc0cbb' 
  AND token = 'SWWvkKnAn0gLKeSgfHjBBq67jRbhq51qELOCIpcl0ho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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