SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '780177895fa072b96ebd48578be542d3fe661c1f9c3b6a593e656f3e9dc98580' 
  AND token = 'B+S+Sz7pQu15IEx9bNgsjg/xAx3TXHTRu+VwaCPULgw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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