SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ca79827a647a8409b9e0a993a114b585a45a6f484485e44510f37ac933901d8' 
  AND token = 'VDl1Ig+DYZsoxdVHh9CUwh/LBBHuR7T3fLhmgqA5hSY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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