SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '965e9e7bf60b486f15182e361225eb9f4fd70908b36e8193dbca768881ebd31f' 
  AND token = '0SBRfIdCUHHRpG6gFqjl0aGKHQCxEHzX5tHVqPyA01I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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