SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'dff982488a416300c31b0f39c2651b35a52f6c2e93ff8b16fdabaf9c6208cd67' 
  AND token = 'NLMA+wUXNqF5/3N2wTH4JX9kyaTk7eeJV6gz1crjCQM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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