Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '257bbc60494134a9f3808a2dc04b3d576204b3c4edee58b59aafacdebae2273c' 
  AND token = 'cVx2kiMqN5xF1pKSSOY0t0it2UGb/7BTalP2KrIE1GU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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