SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce06343694302635735783f87ec9ee19cb2115a476bd7868a714ab0c908f348e' 
  AND token = 'cBbLiw+uSFQyvmmnAPRTXh+Ii82QlTa9qRJEiWRVIBw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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