SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b71e7e511d0d25a77d61c7a09b5a80954e1366f8d1b4f9f80a1c2de7da8069b1' 
  AND token = 'rxm6ZY43hmRVcCWKJgRpL4HERth3f0JJ352c/miT1SY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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