SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f163ff496e4d2acb0759ddb8a9184e4d08ea45f6aad0e2ea123795998747a0c2' 
  AND token = 'qRYoRID+TKYH8kURm3hDF4GEmSJ1LpAXDnUp+gLszDQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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