SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '903668dca50bd54c641110fea87e4d02185f3fdad92d8ce4742bc5e24c3fae38' 
  AND token = 'a9977qobI5GM7WaZ+nfPpH3Ssai0g+1jG3ArkFFbdjA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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