SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ad822fa85abdf425de91afed2b2aa76289c62e93fe95eeeb0dacc688833035a' 
  AND token = 'hIE3FTgd92RQ2MPXqvi8BfL9wU5Lu7yPn64e586hEiw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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