SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9893130e03cc0e0f3fd674cbf4ee1ac2afcbbc960f05202e0668bb0604a2ac53' 
  AND token = 'sMFh64kMmbE3JQ8brChxyq0aPehQVppbf8ZxTlUae80=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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