SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b277d7cbeea23abac4f5cfdb60634cabad6375d931ba945cad3de10072767c4' 
  AND token = 'BS+ypWzRvaaKUt/Ik8MpZiuCkb3RddrDHQ6j45k7aqM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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