SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '53397d865f5c9638e0cbe71711deed630d57573e4ff8c1e8c841a049eb43c16b' 
  AND token = 'ULRJyvRaPMol24AGtZlxk56WSI+eCxvUHlTkBMlpuUM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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