SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f52118dc12793aa2a656e03c34026a7f2187940ef75b39d6f8fe2814ff991c2' 
  AND token = 'cnCbLEhRpph0wVXD+3zKBkc2ZWfGLd+R/88dchkqrpw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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