SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17e20d809795e5bedc10187494c599209d157af899e6d389d0ea9d8207c6e6ab' 
  AND token = 'PP4p/ZD4SCaiBmA5DupsXrX8ctktzTwwL3BT4sP1fQE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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