SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b2638b389f8de9e5d3191bad2fd49a5864fe3c077c9e030827d26cae88b19155' 
  AND token = 'X5RYPaX3xG0/+tvwuTgMHk8ymdT3PSLBvPS/X+w47SQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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