SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e771222cbc48a384902bf0ca0c6b12ed21d2870149a2a5db203952a7902acfe' 
  AND token = 'mRTXYFR+1+shY95DLuYwYHP56Ai2tacoahWFnOQk4Ug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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