SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5be58071c5a7362c608b17067a1921c167862c8b5248548ff03f555d779a718b' 
  AND token = 'jXzhVjCpeFTElY+FU5+yNz2HjT4iByXcR5u6vjsW/gY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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