SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce3afa6f60df659d5fba4587e1fa2f6fd3be86dc2367dca21a0c6e7458e3184b' 
  AND token = 'rgvj+4hQwVn/ow+qr9kLDn/WiN+nkrIPwDze67ChdAg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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