SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58bd441f42fc2b51039381d487abac3194e49e8a66bbb1805647345e7ce71e13' 
  AND token = 'LxUZDPamJKCXZqy9O7m90AFw9vAymDcUpzN1bMBd1tg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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