SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27deeb287db5aafbaa9d5eb14879128fe7e45a15c410f52de5d68802348da22b' 
  AND token = 'AVvBayYNnBNz38u2Bslc+rnaWyrkLJlU3exOya6t9Vs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}