SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a902e549c5870edebaf27c8d202edd0b82728d76ac1f99d4082e7465fa8aee6d' 
  AND token = 'iciWDW6mVO8d9iDXJ3rCRaztgbzs283t7i/MmcROXoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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