SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f45672fa66436bc1afac598767422bb196a24c5d54c89078518f0b5e5653a0e0' 
  AND token = 'rTAxRtKrIlMcb/z+U18b596UXTRyW0gJzF6txG+AUmk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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