SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a52230109cf498cb2244f186954d57bf29626152445952f4165ec0715af955a' 
  AND token = 'dJActKHBPi+FaLI5a55mkXGgSAooQwRHts4ggQEpb18=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}