SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98ad63c132445d317bbc4566a938f3d07784708e826a76e7f7c2267b0b8cfd4a' 
  AND token = 'XoMKNrdAgMSVBwnR5sHjTkf2Zvq34feH7WhHgX+UrNI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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