SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '97521e06574d713db550e220bea02a5300ef5390fd772178dfc0324f42e8b0b6' 
  AND token = 'xPl69TJorjuS6NJIA8PfHLfK5AXrNQOdd2qHOmO6b50=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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