SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '896fa84c07dc7167b2d67dc05767c09871a48129321f8057e89d4305ce537c6d' 
  AND token = 'GqCORts7XijpPCg/cjEmm+Ix8CCnDpE3gvpNDpHiTEM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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