SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc14b0875b53ac5e7052153bc95ea4c9f0b639edc80d74cbb3b6897ef2693099' 
  AND token = '0iGpAG9Dmrc5jF0rDBH3eLEvy9R3xZjOsrApRLU8+U4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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