SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e2d9b321f5ef2ffc59ba3940c2329c9af6fbea05f2ef34f56deeae6ef3c121d0' 
  AND token = 'rszEh7JAxtgOAiKNNLkax52Z5d6uxkSzW3lW7s5OMXc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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