SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'c297bbee2a0c3b7e89b50da2de858430d0472e8bcbb204bf08b185586e855a38' 
  AND token = 'vYF3JPaRkKaIiyMGgM7SbUd3q4u7QPDX50dwAuK+e34=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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