SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41bf093a413f0a5a07044694a04519f98b0fb13835ffa1a433bc3c3323c6e8fc' 
  AND token = '9PSycHAHmCbdJeAu75VyEKfwG10P91eaSC25/fcNBuc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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