SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c43560e278fba23967cf80982cae38e27af56b0ec67541a2ad11f24515cdb51b' 
  AND token = 'qw104bVWSh8ZKpgi6NLSpvvQlimGFyc49HlroDBV9hs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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