SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e75e91181cc090d8a6a7d5ae9b55bb020816c9174ed5a37bdd4a48c627acd019' 
  AND token = 'HXd5wNlKB00TfeFK9/ZPi5Ez+1Xf2fFSyVUfwID9yGI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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